OBJECTIVE To investigate the associations of metformin, serum vitamin B12, calcium supplements, and cognitive impairment in patients with diabetes.
RESEARCH DESIGN AND METHODS Participants were recruited from the Primary Research in Memory (PRIME) clinics study, the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging, and the Barwon region of southeastern Australia. Patients with Alzheimer disease (AD) (n = 480) or mild cognitive impairment (n = 187) and those who were cognitively intact (n = 687) were included; patients with stroke or with neurodegenerative diseases other than AD were excluded. Subgroup analyses were performed for participants who had either type 2 diabetes (n = 104) or impaired glucose tolerance (n = 22).
RESULTS Participants with diabetes (n = 126) had worse cognitive performance than participants who did not have diabetes (n = 1,228; adjusted odds ratio 1.51 [95% CI 1.03–2.21]). Among participants with diabetes, worse cognitive performance was associated with metformin use (2.23 [1.05–4.75]). After adjusting for age, sex, level of education, history of depression, serum vitamin B12, and metformin use, participants with diabetes who were taking calcium supplements had better cognitive performance (0.41 [0.19–0.92]).
CONCLUSIONS Metformin use was associated with impaired cognitive performance. Vitamin B12 and calcium supplements may alleviate metformin-induced vitamin B12 deficiency and were associated with better cognitive outcomes. Prospective trials are warranted to assess the beneficial effects of vitamin B12 and calcium use on cognition in older people with diabetes who are taking metformin.
Might be worthwhile for those of us on Metformin to get our B12 level checked:
Graham
3 comments:
Was there any discussion about whether people who took Metformin might be those more prone to cognitive impairment in the first place? Did people in the control group take other diabetes medications?
I wouldn't be surprised if this were true. Metformin had a strange effect on me - maybe it still does!
It affected my coordination and speech. almost as if I had suffered a stroke. I was told this was unusual but not unheard of. Eventually these side effects wore off-at least I think they did.
Kath
Hi Jan
Unfortunately I don't have access to the full paper so I can't shed any light on the points you raise.
Graham
Post a Comment